Problem: Vanessa is 5 times as old as Gabriela and is also 12 years older than Gabriela. How old is Vanessa?
Answer: We can use the given information to write down two equations that describe the ages of Vanessa and Gabriela. Let Vanessa's current age be $v$ and Gabriela's current age be $g$ $v = 5g$ $v = g + 12$ Now we have two independent equations, and we can solve for our two unknowns. One way to solve for $v$ is to solve the second equation for $g$ and substitute that value into the first equation. Solving our second equation for $g$ , we get: $g = v - 12$ . Substituting this into our first equation, we get the equation: $v = 5$ $(v - 12)$ which combines the information about $v$ from both of our original equations. Simplifying the right side of this equation, we get: $v = 5v - 60$ Solving for $v$ , we get: $4 v = 60$ $v = 15$.